Principia Ethica

Published in 1903, the Principia Ethica is philosopher G. E. Moore's most famous book. It promotes non-naturalist moral realism, or simply non-naturalism. This is the view that goodness exists in some objective sense but cannot be discovered or defined by empirical science. In other words, moral truths are totally distinct and isolated from all other kinds of knowledge (scientific, religious, and even philosophical).